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// Generic ARMv7-A target for bare-metal code - floating point disabled
//
// This is basically the `armv7-unknown-linux-gnueabi` target with some changes
// (listed below) to bring it closer to the bare-metal `thumb` & `aarch64`
// targets:
//
// - `TargetOptions.features`: added `+strict-align`. rationale: unaligned
// memory access is disabled on boot on these cores
// - linker changed to LLD. rationale: C is not strictly needed to build
// bare-metal binaries (the `gcc` linker has the advantage that it knows where C
// libraries and crt*.o are but it's not much of an advantage here); LLD is also
// faster
// - `panic_strategy` set to `abort`. rationale: matches `thumb` targets
// - `relocation-model` set to `static`; also no PIE, no relro and no dynamic
// linking. rationale: matches `thumb` targets
use super::{LinkerFlavor, LldFlavor, PanicStrategy, RelocModel, Target, TargetOptions};
pub fn target() -> Target {
let opts = TargetOptions {
abi: "eabi".into(),
linker_flavor: LinkerFlavor::Lld(LldFlavor::Ld),
linker: Some("rust-lld".into()),
features: "+v7,+thumb2,+soft-float,-neon,+strict-align".into(),
relocation_model: RelocModel::Static,
disable_redzone: true,
max_atomic_width: Some(64),
panic_strategy: PanicStrategy::Abort,
emit_debug_gdb_scripts: false,
c_enum_min_bits: 8,
..Default::default()
};
Target {
llvm_target: "armv7a-none-eabi".into(),
pointer_width: 32,
data_layout: "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64".into(),
arch: "arm".into(),
options: opts,
}
}